Power supply means for percussor apparatus



R C. M SHIRLEY POWER SUPPLY MEANS FOR PERCUSSOR APPARATUS 2 SHEETS-SHEET 1 Jan. 8, 1952 Filed March 5, 1948 J LL INVENTOR,

Jan. 8, 1952 R. c. M SHIRLEY 2,581,806

POWER SUPPLY MEANS FOR PERCUSSOR APPARATUS Filed March 5, 1948 2 SI IEETS-SHEET 2 ,lllllllllllllll llllllllllllllllllllflk mh INVENTOR,

HTTORNEX Patented Jan. 8, 1952 UNITED STATES PATENT OFFICE POWER SUPPLY MEANS FOR PERCUSSOR APPARATUS Robert C. McShirley, Glendale, Calif.

Application March 5, 1948, Serial No. 13,165

3 Claims. (Cl. 318-430) This invention relates to percussors for use in physiotherapy and particularly to a form thereof in which the percussions are produced by a reciprocating motor means energized by an electric current controlled by electronic means.

Heretofore, percussors (also known in the art as concussors have been used in which a rotary motor delivered mechanical impulses to an applicator held in contact with the body of the patient. but such devices employ a crank or cam to convert the rotations into the movement imparted to the applicator; such movement being more like a vibratory movement than a true percussive movement. Such devices have not been as satisfactory as might be due to the fact that the mechanical linkage that converts therotary motion into linear motion produces a slowing up of the rate of linear motion as the crank or cam passes over center and begin its retractive movement. As a result. the applicator does not impart the sharp, quick blow or stroke which is essential to the realization of maximum benefits from percussion techniques. Additionally, such devices have lacked the optimum range of speeds or the ability to deliver true percussive strokes at both high and low frequencies as well as the capacity for independent variation of the force with which percussive strokes are delivered and of the rate of percussion.

With the foregoing considerations in mind, it is an object of the present invention to provide an electrically operated percussor for therapeutic purposes in which the body-contacting implement (hereinafter designated as applicator") is moved at a substantially uniform rate of speed throughout the extent of any length or frequency of percussive stroke.

Another object of the invention is .to provide an electrically operated therapeutic percussor in which both the frequency of percussive strokes and the force applied at each stroke can be independently varied.

Still another object of the invention is to provide an electrically operated percussor for therapeutic purposes in which the percussive strokes are produced by a reciprocating motor mechanism energized by an electrical system employing a thermionic tube.

A still further object of the invention is to provide an electrically operated percussor for. therapeutic purposes in which the applicator and its actuating motor are carried by a freely dirigible hand piece electrically connected to a power source and in which a single control on said hand piece controls both a. power circuit and a control circuit.

A still further object of the invention is to provide a percussion producing instrumentality for therapeutic purposes in which the individual strokes of the body-contacting element are derived from electrical impulses of less duration in time that the time required for each stroke and in which each stroke is completed by the kinetic energy imparted to the element by the said impulses.

A still further object of the invention is to provide an electrically operated percussion apparatus having the above desirable characteristics composed of few parts and which is so constructed and arranged as to be of small size and, consequently, is readily portable and, further, is reliable in operation and economical to manufacture.

With the above objects in View together with such additional objects and advantages as may hereinafter appear, the invention resides in the parts, and in the construction, combination, and arrangement of parts, which, by way of example, is hereinafter described and illustrated in the accompanying drawings, in which:

Fig. l is a side elevation of the hand piece of the apparatus carrying one form of commonly used applicator,

Fig. 2 is a top plan view of the hand piece shown in Fig. 1,

Fig. 3 is a circuit diagram of an electric circuit which is adapted to serve as a source of power for the motor means carried by the hand piece,

Fig. 4 is a longitudinal, sectional, side elevation of the hand piece taken on the line 4-4 of Fig. 2,

Fig. 5 is a transverse sectional view taken on the line 5-5 of Fig. 2,

Fig. 6 is a fragmentary, longitudinal, sectional view taken on the line 56 of Fig. 4,

Fig. 7 is an enlarged front elevation of the reciprocating motor means carried by the hand piece of the apparatus, and

Fig. 8 is a side elevation of the field assembly of the motor means.

Referring to Figs. 1, 2, and 4 to 7 inclusive of the drawings, the hand piece of the apparatus comprises a pistol-shaped frame member I having a hand grip portion 2, said frame member being formed of non magnetic metal or from a suitable plastic material. The distal end of the frame is formed of spaced, forwardly projecting, members 3 and 4, the free ends of which are connected by an end plate 5 secured thereto by screws 6. The opposed inner surfaces of the members 3 and 4, the inner face of the end plate 5, 'andthe shoulders I and 8 at the rear ends of the members 3 and 4 combine to define a cavity or space 9 in which the motor field assembly I is mounted. Cover plates II and I2 secured to the sides of the frame I by screws l3 serve to complete the enclosure of the motor field assembly ill within the space or cavity 9.

The field assembly in comprises rectangular side plates I4 having rectangular openings I 4a and two opposed pole pieces I5 and is formed of shallow U-shaped laminations of soft iron extending between said side plates and having their extremities facing each other as best shown in Fig. 4: the side plates and pole laminations being secured together by a series of rivets I! passing therethrough. Extending between the portions of each side member between the opposed free ends of the pole pieces are coil supporting plates l8 secured to the side members [4, I4 by tabs is bent over the edges of the side members. A coil is carried by these members and extends outwardly through the openings Ida as best shown in Figs. 5, 6, and 8 and the inturned flanges 2i and the ends of the pole pieces i5 and I6 serve to define a passageway 22 in which the motor armature 23 reciprocates.

The armature 23 comprises a series of laminations of rectangular soft iron plates disposed in planes parallel to the planes of the pole laminations and secured together by rivets 24. Brazed or similarly secured to one end of the armature 2,4 is a bearing rod 25 of stainless steel or other non-magnetic material and similarly secured to the opposite end of the armature is a second bearing rod 26 formed of magnetic material; both of said rods being disposed on the same axial line.

The rod 25 is mounted for reciprocation in and extends through a bearing bushing 21 mounted in the end plate 5 and the rod 26 is similarly mounted in a bearing bushing 28 mounted in a bore 29 in the frame I; both of said bushings being so located that the armature is free to reciprocate in the passageway 22 closely adjacent to but without touching the coil supports l8, l8. The rod 25 at its distal end is threaded to receive an applicator 3c and a lock nut 3|. The applicator may be any one of several forms; the form illustrated being formed of resilient rubber and being U-shaped in cross section as best shown in Fig. 2. As is common practice, different forms of applicators may be interchanged for various types of treatment.

The bore 29 extends from the rear side of the frame member I and the rear portion is counterbored as at 32 to provide clearance for a spring guiding sleeve. 33 surrounding the bar 26 and terminating in a screw portion 34 threaded into the outer end of the counterbore 32. .Surrou-nding the bar 26 and bearing against the end of the bushing 23 and the head of a screw 35 carried by the end of the bar 26 is a compression spring t6 tending normally to hold the armature 23 and its supporting bars 24 and 26 moved to one end of its stroke partly out of the. magnetic field of the field assembly against a resilient buffer pad 37 seated on a surface 36 of the frame member I normal to the axis of the bar 26 and forming the rear end of the cavity 9. The extent of forward movement of the armature and the supporting barsunder the influence of the magnetic fieldcreated by energization of the field assembly is limited by a buffer in the form of a resilient collar 39 mounted on the bar 25 adjacent the armature and adapted toengage the bottom 40 of a. recess formed in the inner face of the end plate 5.

Also mounted in the frame member I adjacent the motor-containing cavity 9 is a combin d 75 sides of the rheostat 4i operated by the knob 43.

switch and rheostat assembly 41 actuated by a shaft 42 projecting through the side wall of the frame member and carrying a control knob 43 so located as to be readily accessible to the thumb of the user as best shown in Fig. 1. The switch controls the flow of actuating current to the field coil 20 and the rheostat assists in varying the voltage in the control circuit ina manner hereinafter to be described. As is usual in such constructions, the rheostat, preferably, is ineffective until the knob and shaft have been rotated sufficiently to close the switch.

The power supply apparatus, illustrated diagrammatically in Fig. 3, includes a connection to a source of alternating current 44 with interposed fuses 45, 45. This circuit is opened and closer by a switch 46 and the primary side of a step down transformer is connected in series with the switch 46 and the power source 44. The secondary side of the transformer 41 is connected in series with the primary side of a step up trans former 48 and the secondary winding of the transformer 46 is connected to the input side of a half wave rectifier 49; the output side of which is filtered by condensers 54 and 55 and resistance unit 53a to provide direct current to a voltage dividing circuit controlled in varying degrees by the rheostat 4! in the hand piece and the rheostat 50 in the power supply unit. The rheostat 5! is connected in series with one side of a gas filled diode 52 across which current will not flow until a predetermined voltage is built up in the condenser 53. The other side of the tube 52 is connected to thegrid of a gas filled rectifier tube 56, the plate of which is connected in series with the motor field coil 26 with the interposed rheostat 51 which is mechanically connected to the switch 46. Resistance units 56a and 56b connected across the power source 44 are providedto impose a bias on the cathode of the tube 56. Ad ditionally, a lead connected to one side of the power source terminates in a loop 58 surrounding the exterior of the tube 52.

The effect of this loop is to create an electrostatic field in the vicinity of the electrodes of the tube 52 with incident concentration of the lines of force within the tube and thus operating at each cycle to lower, momentarily, the voltage at which the tube will allow current to flow; siicli momentary or periodic lowering reaching its greatest effect at the top of the cycle when the voltage in the power source 44 is greatest. As the voltage across the tube 52 increases due to the gradual charging of condenser 53 the breakdown point of the tube 52 is being momentarily lowered at the same instants that the voltage peaks in the power source occur. Thus, the time at which current will fiow across the electrodes of the tube 52 to the grid of the tube 56 is reached at the instant ofmaximum voltage in the power source 44, firing the tube 56 with resultant flow of current from the power source across the tube 56 and through the rheostat 51 to the field coil 20 and thence back to the power source until the cycle reverses at which time the current will. cease to flow across the tube 56 until it is fired again.

The hand piece is connected to the power supply unit by a multiple wire flexible cable 56 com taining'five wires, one of which is a ground connection, two of which are connected to opposite sides of the switch operated by the knob 43 and complete the circuit to the field coil 20 and the other'two of which are connected to opposite ssh-gate The cable extends up through a bore 50 in the hand grip and midway of the length of the bore and cable carries a split clamp collar 5| adapted to be compressed and caused to grip the cable by a set screw 62 threaded into the hand grip Z. The bore 80 at the end of the hand grip is threaded to receive nut '63 and an associated coil spring '64 surrounding the cable and the spring is provided with a loop E5 formed by bending one of the coils thereof out of the axial line of the spring whereby the hand piece may be suspended from a hook when not in use. At its other end, the cable provided with a conventional mill tiple contact plug 6'6 adapted to beinserted into a corresponding receptacle carried by "the power supply unit with incident completion of the circuits extending between the power supply and the hand piece. This is desirable to facilitate the packing of the units for transport, but it is not absolutely necessary, since the cable may be permanently connected to the power supply, if desired.

The energizing current is applied to the coil at the instant that the maximum powersource voltage occurs, and is applied. only duringv the remainder of the half cycle in which the tube 55 is fired. Thus it will be realized that the power impulses delivered to the coil 20 are of extremely short duration; being little if any more than a quarter cycle in extent and in thecase of f ED'cycle current, this wouldarnount to about /240 of a second.

By adjustment of the rheostats 4|, 5d and 5!, the rate of charging of the condenser and of the resultant firing of the tube can be varied from 3600 times per minute to rates which may be low as '60 times per minute, and in each instance, the maximum voltage available will be applied to the coil 28. The location of the switch and rheostat unit in the hand piece permits the operator to start and stop the motor means and to vary the frequency of percussion at will during the treatment of a patient without the necessity of turning away to the power supply for that purpose.

As above explained, at each impulse, the armature and the applicator are moved suddenly forward, but the impulse is terminated before the movement is completed. However, the mass of the armature and the applicator provide the necessary kinetic energy to continue the forward movement initiated by the impulse until it is stopped by contact with the patient or with the buffer 39 at which time the spring 36 will start the return movement. At such adjustment of the control circuit that the tube 56 is fired at the higher frequencies, the successive impulses may be delivered before the preceding return movements are completed and, in effect, reduce the length of stroke.

While, visually, these high frequency movements may seem to resemble simple vibration, they are in fact true percussive movements in that the forward movement is at a more rapid rate than the return movement. Regardless of the frequency, the nature of the movement is much like that which would be obtained if the rear end of the rod 26 were to be repeatedly struck with a hammer to produce the forward movement.

. The advantages of manual percussion massage techniques to stimulate the flow of blood and lymph and for other therapeutic purposes are well known but, heretofore, no device has been available that would closely approximate the effect of 15 6 manual percussion with its capacity for variation of both force andfrequency of stroke. The present invention not only achieves this desirable re suit, but also, can continue these movements over periods of time and at frequencies that would be impossible to contmueor to achieve manually.

It will be understood that the particular'form of operating circuit illustrated is by way of example only, and that any other circuit which will deliver "equivalent impulses to the operating motor means and which can be controlled from a freely dirigible hand piece carrying the motor and the applicator shall be considere'd as the equivalent of the above illustrated and described circuit in the combinations hereinafter claimed.

It will also be appreciated that while the power supply circuit above described may find its greatest usefulness in the actuation of therapeutic instruments, it also capable of use as a power supply for any device in which an electrically derived, percussive movement is'desired.

While I have shown and described one form of execution of my invention, '1 do not limit my self to the exact combination disclosed, and the invention includes such modifications of the parts and their equivalents, and of the construction, combination, and arrangement thereof, as come within the purview of the appended claims.

1. A power supply unit for a percussion apparatus having a reciprocable, solenoid actuated element; said unit comprising an input lead a tachableto a source of alternating current, an output lead attachable .to the actuating coil of a percussion apparatus, and means electrically interconnecting said leadsjan'd operative to convert input alternating current into an output current comprising a succession of separate, undirectional, electrical impulses; said means comprising a thermionic rectifier tube having a grid, a cathode, and an anode; said cathode being connected to said input lead and said anode being connected to said output lead, a half Wave rectifier interposed between said input lead and said grid, a diode comprising a pair of spaced electrodes in a gas filled envelope connected in series between said half wave rectifier and said grid,

and means for intermittently reducing the re-' sistance of said diode comprising a conductor having one end thereof connected to said input lead and having the other end thereof termihating in a loop spaced from and surrounding said diode in the region of said electrodes and effective at the instants of peak voltages of input alternating current to create an electrostatic field in the region of said electrodes with resultant reduction of the resistance between said electrodes and initiation of current flow from said half wave rectifier to said grid at such peak voltage instants.

2. A power supply unit for actuation of a percussion apparatus of the type having a reciprooable, solenoid actuated element; said power supply -unit including means for converting input alternating current into a succession of separate, unidirectional electrical power impulses and comprising an input lead attachable to a source of alternating current, an output lead attachable to the solenoid coil of a percussor apparatus, a thermionic rectifier tube having a grid, a cathode and. an anode; said anode being electrically connected to said output lead and said cathode being electrically connected to said input lead, a half wave rectifier including a condenser electrically interconnected between said input lead and said grid, a diode including a pair of electrodes enclosed within a gas filled envelope connected in series between said half wave rectifier and said grid, and means electrically connected to said input lead and having a portion thereof positioned adjacent to said diode effective to create an intermittent electrostatic field in the region of said electrodes which field reaches its maximum intensities at the peak voltages of input current with resultant momentary reductions of the resistance of said diode to values below the capacitanceof said condenser and consequent initiation of current flow to said grid only at the instants of peak voltages of input current.

3. A power supply unit for actuation of a percussion apparatus of the type having a recipe rocable, solenoid actuated element; said power supply unit including means for converting in-- put alternating current into a succession of sepa- I rate, unidirectional electrical power impulses and comprising an input lead attachable to a source of alternating current, an output lead attachable to a percussor apparatus, a thermionic rectifier tube having a grid, a cathode connected to said input lead and an anode connected to said output lead, a half wave rectifier including a condenser electrically connected between said input lead and said grid; said condenser being connected to be charged by successive positive half cycles of input current passing through said half wave rectifier, a diode comprising a pair of spaced electrodes enclosed in a gas filled envelope. con,- nected in series between said half wave rectifier and said grid; said diode normally having a resistance greater than the potential of said condenser when fully charged, and means for mementarily reducing the resistance of said diode to a' value slightly less than the maximum potential .of said condenser; said resistance reducing means comprising a lead connected at one end ,to' said input lead and terminating at its other end in a loop surrounding the envelope of said diode and effective to create an intermittent electrostatic field about said diode; said field reaching its maximum intensities at the peak volt ages of input current with consequent momentary reductions of the resistance of said diode at such peak voltages and initation of current flow from said condenser across said diode to said grid only at or near such peak voltages and resultant firing of said tube and flow of current from said oathode to said anode during the remainder only of such positive half cycle of input current.

ROBERT C. MCSHIRLEY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

